A shoulder replacement, or arthroplasty, is an effective surgical procedure designed to alleviate chronic pain and restore functional mobility in a damaged joint. The operation involves replacing the natural ball and socket components with artificial implants made of metal and plastic. While the surgery can dramatically improve quality of life, it introduces permanent, lifelong restrictions necessary to protect the prosthetic components. These precautions prevent early wear, loosening of the implant from the bone, or fracture, ensuring the longevity of the replacement. Understanding these permanent limitations is important.
Permanent Restrictions on Lifting and Carrying Weight
Patients must observe a strict, lifelong limit on the amount of weight they can lift or carry with the surgical arm. This restriction is often the most significant long-term modification, as excessive static and dynamic loads compromise the implant’s fixation. Most orthopedic surgeons recommend never lifting more than 10 to 15 pounds with the operated arm, though some may allow up to 25 pounds, depending on the specific implant design. The reason for this permanent weight limit is to prevent aseptic loosening. Excessive force increases stress at the bone-implant interface, which can cause the prosthetic components to gradually detach from the surrounding bone. Heavy lifting also accelerates wear on polyethylene socket components, creating debris that contributes to loosening. Common household items such as a full gallon of milk or a heavy suitcase meet or exceed the typical 10-to-15-pound threshold.
Activities Involving High Impact or Repetitive Strain
Activities that involve sudden, high-velocity forces or prolonged, repetitive vibrations must be permanently avoided following shoulder replacement surgery. These dynamic actions transmit shock waves through the joint structure, which can lead to component fracture, instability, or accelerated wear. Contact sports like football, rugby, or wrestling are permanently restricted due to the high risk of catastrophic falls or direct impacts to the joint. Activities requiring a forceful throwing motion, such as aggressive baseball pitching or competitive racket sports, are generally prohibited due to the extreme forces they generate. Prolonged exposure to high-frequency vibration tools, such as using a jackhammer or chopping wood, should also be limited or avoided. These forceful actions can prematurely degrade the artificial joint, increasing the likelihood of early failure and the need for revision surgery.
Understanding Lifetime Limits on Joint Positioning
Permanent restrictions on the angular positioning and extreme movement of the shoulder joint are necessary to maintain stability and prevent dislocation. These limits are particularly stringent for patients who have received a Reverse Total Shoulder Arthroplasty (rTSA), as the new, medialized center of rotation alters the joint’s biomechanics. Even with a traditional total shoulder replacement, patients are advised against habitually pushing up on the arm to stand from a chair or leaning heavily on the arm. These restricted positions and movements are dictated by the implant’s design and the need to prevent mechanical impingement or dislocation.
Reverse Total Shoulder Arthroplasty (rTSA) Restrictions
For rTSA patients, the combination of internal rotation, adduction, and extension is permanently restricted to prevent the joint from popping out of its socket. This specific combination of movements is often encountered when aggressively reaching across the body or forcefully tucking a shirt behind the back. Additionally, movements involving extreme external rotation or reaching too far behind the neck are typically prohibited for life.